Encapsulation film

ABSTRACT

Provided are an encapsulation film, an organic electronic device including the same, and a method of manufacturing the organic electronic device. Particularly, the encapsulation film, which effectively blocks moisture or oxygen entering the organic electronic device from the outside, and has excellent mechanical properties such as handleability and processability, and the organic electronic device including the same are provided.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a National Stage Application of InternationalApplication No. PCT/KR2016/001603 filed on Feb. 17, 2016, which claimsthe benefit of Korean Patent Application No. 10-2015-0024423 filed onFeb. 17, 2015, all of which are hereby incorporated by reference intheir entirety for all purposes as if fully set forth herein.

BACKGROUND

1. Field of the Invention

The present application relates to an encapsulation film, an organicelectronic device (OED) including the same, and a method ofmanufacturing an OED using the same.

2. Discussion of Related Art

An OED is a device including an organic material layer in which electriccharges are exchanged using holes and electrons, and the OED may be, forexample, a photovoltaic device, a rectifier, a transmitter, or anorganic light emitting diode (OLED).

Among the OEDs, an OLED has lower power consumption and a higherresponse speed, and is more advantageous in reducing the thickness of adisplay device or lighting than a conventional light source. Such anOLED also has excellent space utilization, and is expected to be appliedto various fields including all types of portable devices, monitors,notebook computers and TVs.

For commercialization and expanded use of the OLED, the most criticalproblem is durability. Organic materials and metal electrodes includedin the OLED are very easily oxidized by an external factor, for example,moisture. Therefore, a product including an OLED is very sensitive toenvironmental factors. For this reason, various methods have beensuggested to effectively prevent the permeation of oxygen or moistureinto an OED such as an OLED from the outside.

SUMMARY OF THE INVENTION

The present application provides an encapsulation film, which can form astructure capable of effectively blocking moisture or oxygen entering anorganic electronic device (OED) from the outside, and has excellentmechanical properties such as a handleability and processability.

The present application relates to an encapsulation film. Theencapsulation film may be applied to encapsulate or capsulate an OEDsuch as the OLED.

The term “organic electronic device” used herein refers to a product ordevice having a structure including an organic material layer in whichelectric charges are exchanged using holes and electrons between a pairof facing electrodes, and examples of the OED may include, but thepresent application is not limited to, a photovoltaic device, arectifier, a transmitter, and an OLED. In an exemplary embodiment of thepresent application, the OED may be an OLED.

The exemplary encapsulation film 10 may include, as shown in FIG. 1, aprotective layer 13, a metal layer 12 and an encapsulation layer 11,which are sequentially formed. Here, the protective layer may have atensile modulus of 0.01 to 500 MPa at 25° C. The encapsulation layer maycontain a pressure-sensitive adhesive composition or an adhesivecomposition. The present application relates to an encapsulation filmprovided by integrating the protective layer, the metal layer and theencapsulation layer as described above. However, when the film isprovided as described above, the warpage of a panel may occur in a hightemperature process resulting in an alignment error in each layer. Inthe present application, the warpage of the panel occurring because ofthe characteristics of a film for encapsulating an organic electronicelement undergoing a high temperature process may be prevented, and analignment error of the encapsulation film in which all components areintegrated may be minimized by controlling the range of a tensilemodulus of the protective layer.

In one exemplary embodiment, the protective layer and the metal layer ofthe present application may satisfy General Equation 1.T _(p) /T _(m)≧1  [General Equation 1]

In General Equation 1, T_(p) is a thickness of the protective layer, andT_(m) is a thickness of the metal layer. A ratio of the thickness of theprotective layer to the thickness of the metal layer (T_(p)/T_(m)) maybe 1 or more, 1.3 or more, 1.5 or more, 1.8 or more, 2 or more, or 2.1or more. The thickness of the protective layer may be in a range of 40to 400 μm, 50 to 380 μm, 55 to 350 μm, 60 to 330 μm, 70 to 300 μm, or 80to 280 μm. Also, the thickness of the metal layer may be in a range of10 to 100 μm, 11 to 90 μm, 12 to 80 μm, 13 to 70 μm, 14 to 60 μm, 15 to50 μm, or 16 to 45 μm. In the present application, damage to the organicelectronic element caused by an external impact in a process ofmanufacturing an OED may be prevented by controlling the thickness ofthe protective layer to be the above-mentioned value or higher. Also,the present application may provide an OED having flexibility bycontrolling the thickness of the metal layer to be the above value orless. Accordingly, to provide the encapsulation film, which hasflexibility to be applied to a flexible display such as an OED and iscapable of preventing damage, for example, a dent caused by an externalimpact during the process of manufacturing an OED, the thickness of themetal layer and the thickness of the protective layer may satisfy thethickness ratio of General Equation 1. Meanwhile, when the thickness ofthe protective layer is increased in a predetermined range or more, thedamage generated in the process may be prevented, but the OED may havewarpage at high temperature. Therefore, the thickness of the protectivelayer may be 400 μm or less. Also, as the protective layer of theencapsulation film satisfies the above range of the tensile modulus, thepresent application may provide an encapsulation film for an OED, whichcan prevent damage to the element and the warpage of a panel, minimizethe alignment error of the OED, and be applied to a flexible display.

In an exemplary embodiment of the present application, the metal layerof the encapsulation film may be transparent or opaque. Meanwhile, theterm “metal layer” used herein may be used to mean the same as aninorganic layer. The metal layer may be formed by depositing a metal ona thin metal foil or a polymer base film. The polymer base layer may bethe above-described protective layer. For the metal layer, any materialhaving thermal conductivity and a moisture blocking property may be usedwithout limitation. The metal layer may include any one of a metal, ametal oxide, a metal nitride, a metal carbide, a metal oxynitride, ametal oxyboride, and mixtures thereof. For example, the metal layer mayinclude an alloy in which one or more metal elements or non-metalelements are added to one metal, for example, the alloy may be aniron-nickel alloy or stainless steel (SUS). Also, in an exemplaryembodiment, the metal layer may include copper, nickel, aluminum,silicon oxide, aluminum oxide, titanium oxide, indium oxide, tin oxide,indium tin oxide, tantalum oxide, zirconium oxide, niobium oxide ormixtures thereof. The metal layer may be deposited using a means forelectrolysis, rolling, heated evaporation, electron beam evaporation,sputtering, reactive sputtering, chemical vapor deposition, plasmachemical vapor deposition or electron cyclotron resonance plasma sourcechemical vapor deposition. In one exemplary embodiment of the presentapplication, the metal layer may be deposited by reactive sputtering.

Preferably, the metal layer may have a thermal conductivity of 50 W/mKor more, 60 W/mK or more, 70 W/mK or more, 80 W/mK or more, 90 W/mK ormore, 100 W/mK or more, 110 W/mK or more, 120 W/mK or more, 130 W/mK ormore, 140 W/mK or more, 150 W/mK or more, 200 W/mK or more, or 250 W/mKor more. Due to the high thermal conductivity, heat generated at alaminating interface in a process of laminating the metal layer may bemore rapidly emitted. Also, because of the high thermal conductivity,heat accumulated in the operation of the OED may be quickly emitted tothe outside, and thus a temperature of the OED itself may be maintainedlower, and cracks and defects may be reduced.

The term “thermal conductivity” used herein may be a degree of theability to transfer heat by conduction, and a unit may be W/mK. The unitis a degree of heat transmission of a material at the same temperatureand distance, and refers to a unit (watt) of heat with respect to a unit(meter) of a distance and a unit (kelvin) of a temperature.

Also, the metal layer may have a tensile modulus of 10,000 to 250,000MPa, 20,000 to 240,000 MPa, or 30,000 to 230,000 MPa at 25° C. As thetensile modulus of the metal layer is controlled in the above range, thepresent application can provide an encapsulation film for an OED, whichcan prevent the warpage of a panel, minimize an alignment error, and beapplied to a flexible display.

As described above, the encapsulation film may include a protectivelayer. The protective layer may prevent corrosion when the metal layeris in contact with moisture, and damage caused by folding or bending inthe process.

Also, as described above, the protective layer may have a tensilemodulus of 0.01 to 500 MPa at 25° C. Measurement of the tensile modulusmay be performed by a method known in the art. For example, a specimenis prepared by coating a protective layer to a thickness of 80 μm andcutting the protective layer into a size of 50 mm×10 mm (length×width)in a lengthwise direction, which is the coating direction during themanufacture of the protective layer, and then both ends of the specimenare taped in the lengthwise direction until only 25 mm of the specimenremains. Subsequently, a tensile modulus is measured by stretching thespecimen by grabbing the taped parts at 1 mm/min, and 25° C. In oneexemplary embodiment, the tensile modulus of the protective layer may bein a range of 0.01 to 500 MPa, 0.1 to 450 MPa, 0.5 to 400 MPa, or 1 to350 MPa at 25° C. The protective layer of the present application mayhave a coefficient of linear expansion of 60 ppm/K or more or 100 ppm/Kor more, and 500 ppm/K or less. The protective layer has the low tensilemodulus as described above even though having a high coefficient oflinear expansion. Therefore, when the encapsulation film is applied toan OED, even though the encapsulation film is contracted or expanded athigh temperature, step differences between layers constituting theencapsulation film may be minimized and the warpage of a panel may beprevented.

In one exemplary embodiment, the protective layer may contain a resincomponent. A material constituting the protective layer is notparticularly limited as long as it satisfies the above range of thetensile modulus. In one exemplary embodiment, the resin componentconstituting the protective layer may be, but is not limited to, one ormore selected from the group consisting of polyorganosiloxane, apolyimide, a styrene-based resin or elastomer thereof, apolyolefin-based resin or elastomer thereof, a polyoxyalkylene-basedresin or elastomer thereof, a polyester-based resin or elastomerthereof, a polyvinylchloride-based resin or elastomer thereof, apolycarbonate-based resin or elastomer thereof, apolyphenylenesulfide-based resin or elastomer thereof, a polyamide-basedresin or elastomer thereof, an acrylate-based resin or elastomerthereof, an epoxy-based resin or elastomer thereof, a silicone-basedresin or elastomer thereof, and a fluorine-based resin or elastomerthereof. The resin component may have a glass transition temperature ofless than 0° C., less than −10° C., less than −30° C., less than −50°C., or less than −60° C. Here, the glass transition temperature may be aglass transition temperature after UV rays are applied at a dose ofabout 1 J/cm² or more; or a glass transition temperature after UVirradiation and additional heat-curing.

Also, the protective layer may further contain a magnetic substance.When the magnetic substance is contained in the protective layer, aprocess for the integrated encapsulation film by magnetic force becomespossible, and thus convenience of the process is ensured andproductivity is improved. In one exemplary embodiment, the magneticsubstance may be one or more selected from the group consisting ofFe₃O₄, Fe₂O₃, MnFe₂O₄, BaFe₁₂O₁₉, SrFe₁₂O₁₉, CoFe₂O₄, Fe, CoPt, andFePt. The magnetic substance may constitute the protective layertogether with the resin component of the protective layer in the form ofpowder. Also, in an exemplary embodiment of the present application, themagnetic substance may be included at 20 to 400 parts by weight, 50 to400 parts by weight, 60 to 350 parts by weight, 70 to 300 parts byweight, or 80 to 250 parts by weight with respect to 100 parts by weightof the resin component. As the magnetic substance is contained at theabove value or more, the film may be fixed by magnets with a sufficientmagnetic force. Therefore, an additional process is not required to fixthe film, and thus the productivity is improved.

Also, the thermal conductivity of the protective layer may be 0.5 W/mKor more, 0.7 W/mK or more, 1 W/mK or more, 5 W/mK or more, 10 W/mK ormore, or 20 W/mK or more, and the upper limit may be, but is notparticularly limited to, 500 W/mK or less. In one exemplary embodiment,the protective layer may include a thermally conductive filler. Thethermally conductive filler may be a material known in the art, whichmay include, for example, one or more selected from the group consistingof aluminum oxide, magnesium oxide, calcium oxide, calcium carboxide,boron nitride, aluminum nitride, silicon carbide and aluminum hydroxide.The thermally conductive filler may be included at 200 to 1500 parts byweight, 300 to 1400 parts by weight, 400 to 1300 parts by weight, or 450to 1200 parts by weight with respect to 100 parts by weight of the resincomponent constituting the protective layer.

In one exemplary embodiment, the encapsulation film may include anencapsulation layer. In one exemplary embodiment, the encapsulationlayer may have a single layer or a multilayer structure having two ormore layers. When the encapsulation layer is composed of two or morelayers, a composition of each layer of the encapsulation layer may bethe same as or different from each other. In one exemplary embodiment,the encapsulation layer may be a pressure-sensitive adhesive layercontaining a pressure-sensitive adhesive composition. Also, theencapsulation layer may be an adhesive layer containing an adhesivecomposition.

In an exemplary embodiment of the present application, the encapsulationlayer may contain an encapsulation resin. The encapsulation resin mayhave a glass transition temperature of less than 0° C., less than −10°C., less than −30° C., less than −50° C., or less than −60° C. Here, theglass transition temperature may be a glass transition temperature afterUV rays are applied at a dose of about 1 J/cm² or more; a glasstransition temperature after UV irradiation and additional heat-curing.

In one exemplary embodiment, the encapsulation resin may be astyrene-based resin or elastomer thereof, a polyolefin-based resin orelastomer thereof, other elastomers, a polyoxyalkylene-based resin orelastomer thereof, a polyester-based resin or elastomer thereof, apolyvinylchloride-based resin or elastomer thereof, apolycarbonate-based resin or elastomer thereof, apolyphenylenesulfide-based resin or elastomer thereof, a mixture ofhydrocarbons, a polyamide-based resin or elastomer thereof, anacrylate-based resin or elastomer thereof, an epoxy-based resin orelastomer thereof, a silicone-based resin or elastomer thereof, afluorine-based resin or elastomer thereof, or mixtures thereof.

Here, the styrene-based resin or elastomer thereof may be, for example,a styrene-ethylene-butadiene-styrene (SEBS) block copolymer, astyrene-isoprene-styrene (SIS) block copolymer, anacrylonitrile-butadiene-styrene (ABS) block copolymer, anacrylonitrile-styrene-acrylate (ASA) block copolymer, astyrene-butadiene-styrene (SBS) block copolymer, a styrene-basedhomopolymer, or mixtures thereof. The olefin-based resin or elastomermay be, for example, a high-density polyethylene-based resin orelastomer, a low-density polyethylene-based resin or elastomer, apolypropylene-based resin or elastomer, or mixtures thereof. Theelastomer may be, for example, an ester-based thermoplastic elastomer,an olefin-based elastomer, a silicone-based elastomer, an acryl-basedelastomer, or mixtures thereof. Among these, the olefin-basedthermoplastic elastomer may be a polybutadiene resin or elastomer or apolyisobutylene resin or elastomer. The polyoxyalkylene-based resin orelastomer may be, for example, a polyoxymethylene-based resin orelastomer, a polyoxyethylene-based resin or elastomer, or mixturesthereof. The polyester-based resin or elastomer may be, for example, apolyethylene terephthalate-based resin or elastomer, a polybutyleneterephthalate-based resin or elastomer, or mixtures thereof. Thepolyvinylchloride-based resin or elastomer may be, for example,polyvinylidene chloride. The mixture of hydrocarbons may be, forexample, hexatriacotane or paraffin. The polyamide-based resin orelastomer may be, for example, nylon. The acrylate-based resin orelastomer may be, for example, polybutyl(meth)acrylate. The epoxy-basedresin or elastomer may be, for example, a bisphenol-type such as abisphenol A-type, a bisphenol F-type, a bisphenol S-type, and ahydrogenated product thereof; a novolac-type such as a phenolnovolac-type or a cresol novolac-type; a nitrogen-containing ring-typesuch as a triglycidylisocyanurate-type or a hydantoin-type; analicyclic-type; an aliphatic-type; an aromatic-type such as anaphthalene-type or a biphenyl-type; a glycidyl-type such as aglycidylether-type, a glycidylamine-type, or a glycidylester-type; adicyclo-type such as a dicyclopentadiene-type; an ester-type; anetherester-type; or mixtures thereof. The silicone-based resin orelastomer may be, for example, polydimethylsiloxane. In addition, thefluorine-based resin or elastomer may be a polytrifluoroethylene resinor elastomer, a polytetrafluoroethylene resin or elastomer, apolychlorotrifluoroethylene resin or elastomer, apolyhexafluoropropylene resin or elastomer, polyvinylidene fluoride,polyvinyl fluoride, polyethylenepropylene fluoride, or mixtures thereof.

A listed resin or elastomer may be grafted with maleic anhydride,copolymerized with another listed resin or elastomer or a monomer toprepare a resin or elastomer, or modified by another compound. Thecompound may be a carboxyl-terminated butadiene-acrylonitrile copolymer.

In one exemplary embodiment, the encapsulation layer may include anolefin-based elastomer, a silicone-based elastomer or an acryl-basedelastomer of the above-described types as the encapsulation resin, butthe present application is not limited thereto.

In an exemplary embodiment of the present application, the encapsulationresin may be an olefin-based resin. In one exemplary embodiment, theolefin-based resin may be a copolymer of diene and an olefin-basedcompound including a carbon-carbon double bond. Here, the olefin-basedcompound may include isobutylene, propylene or ethylene, and the dienemay be a monomer which can be polymerized with the olefin-based compoundand include, for example, 1-butene, 2-butene, isoprene or butadiene.That is, as the encapsulation resin of the present application, forexample, a homopolymer of an isobutylene monomer, a copolymer preparedby copolymerizing an isobutylene monomer and another monomer capable ofbeing polymerized therewith, or mixtures thereof may be used. In oneexemplary embodiment, the copolymer of the olefin-based compoundincluding one carbon-carbon double bond and diene may be butyl rubber.As a specific resin is used as described above, a moisture blockingproperty to be realized in the present application may be satisfied.Also, the conventional isobutylene polymer has a low moisturetransmission rate and low thermal resistance, and in the presentinvention, a specific crosslinked structure may be realized in theencapsulation layer to improve moisture resistance and thermalresistance.

In the encapsulation layer, the resin or elastomer component may have aweight average molecular weight (Mw) for the pressure-sensitive adhesivecomposition to be molded in a film shape. For example, the resin orelastomer may have a weight average molecular weight of about 100,000 to2,000,000, 100,000 to 1,500,000, or 100,000 to 1,000,000. The term“weight average molecular weight” used herein refers to a conversionvalue for standard polystyrene measured by gel permeation chromatography(GPC). However, the resin or elastomer component does not necessarilyneed the above-described weight average molecular weight. For example,when the molecular weight of the resin or elastomer is not enough toform a film, a separate binder resin may be mixed in thepressure-sensitive adhesive composition.

In another exemplary embodiment, the encapsulation resin according tothe present application may be a curable resin. A specific type of thecurable resin that can be used in the present application is notparticularly limited, and various heat-curable or photocurable resinsknown in the art may be used. The term “heat-curable resin” refers to aresin that can be cured by a suitable heat application or aging process,and the term “photocurable resin” refers to a resin that can be cured byirradiation with electromagnetic waves. Also, the curable resin may be adual curable resin including both of heat-curable and photocurablecharacteristics.

In the present application, a specific type of the curable resin is notparticularly limited, and one having the above-described characteristicsmay be used. For example, the curable resin may have an adhesiveproperty after being cured, and may be a resin including one or moreheat-curable functional groups, for example, a glycidyl group, anisocyanine group, a hydroxyl group, an isocyanine group, a hydroxylgroup, a carboxyl group or an amide group, or a resin including one ormore functional groups that can be cured by irradiation withelectromagnetic waves, for example, an epoxide group, a cyclic ethergroup, a sulfide group, an acetal group or a lactone group. Also, aspecific type of the above-described resin may be an acryl resin, apolyester resin, an isocyanine resin or an epoxy resin, but the presentapplication is not limited thereto.

In the present application, as the curable resin, an aromatic oraliphatic, or linear or branched epoxy resin may be used. In oneexemplary embodiment of the present application, as an epoxy resinhaving at least two functional groups, an epoxy equivalent weight of 180to 1,000 g/eq may be used. Characteristics such as adhesive performanceand a glass transition temperature of a cured product may be effectivelymaintained by using the epoxy resin having the above range of the epoxyequivalent weight. Such an epoxy resin may be one or a mixture of atleast two of a cresol novolac epoxy resin, a bisphenol A-type epoxyresin, a bisphenol A-type novolac epoxy resin, a phenol novolac epoxyresin, a tetrafunctional epoxy resin, a biphenyl-type epoxy resin, atriphenolmethane-type epoxy resin, an alkyl-modified triphenolmethaneepoxy resin, a naphthalene-type epoxy resin, a dicyclopentadiene-typeepoxy resin, and a dicyclopentadiene-modified phenol-type epoxy resin.

In the present application, as a curable resin, an epoxy resin having acyclic structure in a molecular structure may be used, and an epoxyresin including an aromatic group (for example, a phenyl group) may beused. When the epoxy resin includes an aromatic group, a cured productmay have excellent thermal and chemical stabilities and low moistureabsorbance, thereby enhancing the reliability of an encapsulationstructure of the OED. A specific example of the epoxy resin containingan aromatic group that can be used in the present application may be,but is not limited to, one or a mixture of at least two of abiphenyl-type epoxy resin, a dicyclopentadiene-type epoxy resin, anaphthalene-type epoxy resin, a dicyclopentadiene-modified phenol-typeepoxy resin, a cresol-based epoxy resin, a bisphenol-based epoxy resin,a xyloc-based epoxy resin, a multifunctional epoxy resin, a phenolnovolac epoxy resin, a triphenolmethane-type epoxy resin, and analkyl-modified triphenolmethane epoxy resin.

In the present application, also, as the epoxy resin, a silane-modifiedepoxy resin, and, a silane-modified epoxy resin having an aromatic groupmay be used. When such an epoxy resin that is modified with a silane andthus structurally has a silane group is used, adhesion of the OED to aglass substrate or a substrate inorganic material is maximized, and awater barrier property or durability and reliability may be enhanced.Such a specific type of the epoxy resin that can be used in the presentapplication is not particularly limited, and the resin may be easilyobtained from a manufacturer, for example, Kukdo Chemical, Co., Ltd.

Also, the encapsulation layer of the present application may include anactive energy ray polymerizable compound which has a high compatibilitywith an encapsulation resin, and may form a specific crosslinkedstructure with the encapsulation resin.

For example, the encapsulation layer of the present application mayinclude a multifunctional active energy ray polymerizable compoundcapable of being polymerized with the encapsulation region byirradiation with an active energy ray. The active energy raypolymerizable compound may refer to a compound including two or morefunctional groups capable of participating in a polymerization reactionby irradiation with an active energy ray, for example, functional groupsincluding an ethylene-like unsaturated double bond such as an acryloylor methacryloyl group, and functional groups such as an epoxy or oxetanegroup.

As a multifunctional active energy ray polymerizable compound, forexample, a multifunctional acrylate (MFA) may be used.

Also, the multifunctional active energy ray polymerizable compoundcapable of being polymerized by the irradiation with the active energyray may satisfy Formula 1. Also, the active energy ray polymerizablecompound may be included at 5 to 30 parts by weight, 5 to 25 parts byweight, 8 to 20 parts by weight, 10 to 18 parts by weight, or 12 to 18parts by weight with respect to 100 parts by weight of the encapsulationresin.

In Formula 1, R₁ is hydrogen or an alkyl group having 1 to 4 carbonatoms, n is an integer of 2 or higher, and X is a residue derived from alinear, branched or cyclic alkyl group having 3 to 30 carbon atoms.Here, when X is a residue derived from a cyclic alkyl group, X may be aresidue derived from a cyclic alkyl group having 3 to 30, 6 to 28, 8 to22, or 12 to 20 carbon atoms. Also, when X is a residue derived from alinear alkyl group, X may be a residue derived from a linear alkyl grouphaving 3 to 30, 6 to 25, or 8 to 20 carbon atoms. Also, when X is aresidue derived from a branched alkyl group, X may be a residue derivedfrom a branched alkyl group having 3 to 30, 5 to 25, or 6 to 20 carbonatoms.

The term “residue derived from an alkyl group” used herein may refer toa residue of a specific compound, for example, an alkyl group. In anexemplary embodiment, in Formula 1, when n is 2, X may be an alkylenegroup. Also, when n is 3 or higher, two or more hydrogen atoms arereleased from an alkyl group of X, and may be bound to a (meth)acryloylgroup of Formula 1.

The term “alkyl group” used herein may be, unless particularly definedotherwise, an alkyl group having 1 to 30, 1 to 25, 1 to 20, 1 to 16, 1to 12, 1 to 8, or 1 to 4 carbon atoms. The alkyl group may have alinear, branched or cyclic structure, and may be arbitrarily substitutedwith at least one substituent.

Also, the term “alkylene group” or “alkylidene group” used herein maybe, unless particularly defined otherwise, an alkylene or alkylidenegroup having 2 to 30, 2 to 25, 2 to 20, 2 to 16, 2 to 12, 2 to 10, or 2to 8 carbon atoms. The alkylene group or an alkylidene group may belinear, branched or cyclic. Also, the alkylene or alkylidene group maybe arbitrarily substituted with at least one substituent.

The term “alkoxy group” used herein may be, unless particularly definedotherwise, an alkoxy group having 1 to 20, 1 to 16, 1 to 12, 1 to 8, or1 to 4 carbon atoms. The alkyl group may have a linear, branched orcyclic structure. Also, the alkoxy group may be arbitrarily substitutedwith at least one substituent.

The multifunctional active energy ray polymerizable compound capable ofbeing polymerized by the irradiation with an active energy ray may beused without limitation as long as Formula 1 is satisfied. For example,the compound may be 1,4-butanediol di(meth)acrylate, 1,3-butylene glycoldi(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,8-octanedioldi(meth)acrylate, 1,12-dodecanediol di(meth) acrylate, neophentyl glycoldi(meth) acrylate, dicyclopentanyl di(meth)acrylate,cyclohexane-1,4-dimethanol di(meth)acrylate, tricyclodec anedimethanol(meth)diacrylate, dimethylol dicyclopentane di(meth)acrylate, neopentylglycol modified trimethylpropane di(meth)acrylate, adamantanedi(meth)acrylate, trimethylolpropane tri(meth)acrylate, or mixturesthereof.

As the multifunctional active energy ray polymerizable compound, forexample, a compound having a molecular weight of less than 1,000 andincluding two or more functional groups may be used. In this case, themolecular weight may refer to a weight average molecular weight or aconventional molecular weight. A ring structure included in themultifunctional active energy ray polymerizable compound may be any oneof a carbocyclic structure, a heterocyclic structure, a monocyclicstructure or a polycyclic structure.

In an exemplary embodiment of the present application, the encapsulationlayer may further include a radical initiator. The radical initiator maybe a photoinitiator or a thermal initiator. A specific type of thephotoinitiator may be suitably selected by considering a curing rate andyellowing probability. For example, a benzoin-based,hydroxyketone-based, aminoketone-based or phosphine oxide-basedphotoinitiator may be used, and specifically, benzoin, benzoinmethylether, benzoin ethylether, benzoin isopropylether, benzoinn-butylether, benzoin isobutylether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone,2,2-diethoxy-2-phenylacetophenone,2-hydroxy-2-methyl-1-phenylpropane-1-one,1-hydroxycyclohexylphenylketone,2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propane-1-one,4-(2-hydroxyethoxy)phenyl-2-(hydroxy-2-propyl)ketone, benzophenone,p-phenylbenzophenone, 4,4′-diethylaminobenzophenone,dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone,2-t-butylanthraquinone, 2-amino anthraquinone, 2-methylxanthone,2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone,2,4-diethylthioxanthone, benzyldimethylketal, acetophenonedimethylketal, p-dimethylamino benzoic acid ester, oligo[2-hydroxy-2-methyl-1-[4-(1-methylvinyl) phenyl]propanone] or2,4,6-trimethylbenzoyl-diphenyl-phosphineoxide may be used.

The radical initiator may be included at 0.2 to 20 parts by weight, 0.5to 18 parts by weight, 1 to 15 parts by weight, or 2 to 13 parts byweight with respect to 100 parts by weight of the active energy raypolymerizable compound. Therefore, a reaction of the active energy raypolymerizable compound may be effectively induced, and degradation ofthe physical properties of the encapsulation layer due to a residualcomponent after curing may be prevented.

In one exemplary embodiment, the encapsulation layer may further includea heat-curable compound. The heat-curable compound may include theabove-described multifunctional acrylate. Such a multifunctionalacrylate may be crosslinked by the above-described thermal radicalinitiator or curing agent.

In an exemplary embodiment of the present application, the encapsulationlayer of the encapsulation film may further include a curing agentaccording to the type of the encapsulation resin. For example, a curingagent capable of forming a crosslinking structure by a reaction with theabove-described encapsulation resin may be further included.

A suitable type of the curing agent may be selected and used accordingto the type of the encapsulation resin or functional group included inthe resin.

In one exemplary embodiment, when the encapsulation resin is an epoxyresin, as a curing agent for an epoxy resin known in the art, forexample, one or two or more of an amine curing agent, an imidazolecuring agent, a phenol curing agent, a phosphorus curing agent, and anacid anhydride curing agent may be used, but the present application isnot limited thereto.

In one exemplary embodiment, the curing agent may be an imidazolecompound, which has a solid phase at high temperature and has a meltingpoint or decomposition temperature of 80° C. or more, may be used. Sucha compound may be, for example, 2-methyl imidazole, 2-heptadecylimidazole, 2-phenyl imidazole, 2-phenyl-4-methyl imidazole or1-cyanoethyl-2-phenyl imidazole, but the present application is notlimited thereto.

A content of the curing agent may be selected according to a compositionof the composition, for example, the type or ratio of the encapsulationresin. For example, the curing agent may be included at 1 to 20 parts byweight, 1 to 10 parts by weight, or 1 to 5 parts by weight with respectto 100 parts by weight of the encapsulation resin. However, the weightratio may be changed by the type and ratio of the encapsulation resin orfunctional group thereof, or a crosslinking density to be realized.

When the encapsulation resin may be a resin that can be cured by theirradiation with an active energy ray, as an initiator, for example, acationic photopolymerization initiator may be used.

As the cationic photopolymerization initiator, an onium salt- ororganometallic salt-based ionized cationic initiator, an organic silane-or latent sulfonic acid-based ionized cationic photopolymerizationinitiator, or a non-ionized cationic photopolymerization initiator maybe used. The onium salt-based initiator may be a diaryliodonium salt, atriarylsulfonium salt, or an aryldiazonium salt, the organometallicsalt-based initiator may be iron arene, the organic silane-basedinitiator may be o-nitrobenzyl triaryl silyl ether, triaryl silylperoxide, or acyl silane, and the latent sulfonic acid-based initiatormay be α-sulfonyloxyketone or α-hydroxymethylbenzoin sulfonate, but thepresent application is not limited thereto.

In one exemplary embodiment, as the cationic initiator, an ionizedcationic photopolymerization initiator may be used.

In one exemplary embodiment, the encapsulation layer may further includea tackifier, which is preferably a hydrogenated cyclic olefin-basedpolymer. As the tackifier, for example, a hydrogenated petroleum resinobtained by hydrogenating a petroleum resin may be used. Thehydrogenated petroleum resin may be partially or completelyhydrogenated, or a mixture of such resins may be used. For thetackifier, one that has a high compatibility with a pressure-sensitiveadhesive composition, an excellent moisture blocking property and a lowcontent of a volatile organic component may be selected. As a specificexample of the hydrogenated petroleum resin, a hydrogenatedterpene-based resin, a hydrogenated ester-based resin or a hydrogenateddicyclochloropentadiene-based resin may be used. A weight averagemolecular weight of the tackifier may be about 200 to 5,000. The contentof the tackifier may be suitably adjusted as necessary. For example, acontent of the tackifier may be selected by considering a gel contentwhich will be described below, and according to an exemplary embodiment,may be included at 5 to 100 parts by weight, 8 to 95 parts by weight, 10to 93 parts by weight or 15 to 90 parts by weight with respect to 100parts by weight of a solid content of the pressure-sensitive adhesivecomposition.

The encapsulation layer may further include a moisture absorbent whenneeded. The term “moisture absorbent” may refer to a material capable ofremoving moisture or vapor which has permeated into an encapsulationfilm that will be described below by a chemical reaction therewith. Whenthe encapsulation layer includes the moisture absorbent, during theformation of a film, optical transmittance that will be described belowmay not be satisfied, instead, an excellent moisture blocking propertymay be realized. In detail, the encapsulation layer, when formed in afilm, may be applied to encapsulate an OED. In this case, when theencapsulation layer may include none or a small amount of the moistureabsorbent, it may be applied to encapsulate a top emission-type OED; orwhen the encapsulation layer may include the moisture absorbent, therebyexhibiting an excellent moisture blocking property, it may be applied toencapsulate a bottom emission-type OED, but the present application isnot limited thereto.

For example, the moisture absorbent may be present in a uniformlydispersed state in the encapsulation layer or encapsulation film. Here,the uniformly dispersed state may mean a state in which the moistureabsorbent is present at the same or substantially the same density inany part of the encapsulation layer or encapsulation film. As themoisture absorbent that can be used herein, for example, a metal oxide,a sulfate or an organic metal oxide may be used. In detail, as anexample of the sulfate, magnesium sulfate, sodium sulfate, or nickelsulfate may be used, and as an example of the organic metal oxide,aluminum oxide octylate may be used. Here, as a specific example of themetal oxide, phosphorous pentoxide (P₂O₅), lithium oxide (Li₂O), sodiumoxide (Na₂O), barium oxide (BaO), calcium oxide (CaO) or magnesium oxide(MgO) may be used, and an example of the metal salt, a sulfate such aslithium sulfate (Li₂SO₄), sodium sulfate (Na₂SO₄), calcium sulfate(CaSO₄), magnesium sulfate (MgSO₄), cobalt sulfate (CoSO₄), galliumsulfate (Ga₂(SO₄)₃), titanium sulfate (Ti(SO₄)₂) or nickel sulfate(NiSO₄), or a metal halide such as calcium chloride (CaCl₂), magnesiumchloride (MgCl₂), strontium chloride (SrCl₂), yttrium chloride (YCl₃),copper chloride (CuCl₂), cesium fluoride (CsF), tantalum fluoride(TaF₅), niobium fluoride (NbF₅), lithium bromide (LiBr), calcium bromide(CaBr₂), cesium bromide (CeBr₃), selenium bromide (SeBr₄), vanadiumbromide (VBr₃), magnesium bromide (MgBr₂), barium iodide (BaI₂) ormagnesium iodide (MgI₂); or a metal chlorate such as barium perchlorate(Ba(ClO₄)₂) or magnesium perchlorate (Mg(ClO₄)₂) may be used, but thepresent application is not limited thereto. As the moisture absorbentthat can be included in the encapsulation layer, one or two or more ofthe above-described components may be used. In one exemplary embodiment,when two or more of the moisture absorbents are used, calcined dolomitemay be used.

Such a moisture absorbent may be controlled in a suitable size accordingto its use. In one exemplary embodiment, an average particle size of themoisture absorbent may be controlled to about 10 to 15000 nm. Since areaction speed of the moisture absorbent with moisture is not too fast,the moisture absorbent having a size in the above range can be easilystored, not damage an element to be encapsulated, and effectively removemoisture.

A content of the moisture absorbent may be suitably selected byconsidering a desired blocking property without particular limitation.

The encapsulation layer may also include a moisture blocker when needed.The term “moisture blocker” used herein may be a material that has noreactivity with moisture or can prevent or interfere with the movementof moisture or vapor in a film. As the moisture blocker, one or two ormore of clay, talc, needle-like silica, plate-like silica, poroussilica, zeolite, titania and zirconia may be used. Also, a surface ofthe water blocker may be treated with an organic modifier to facilitatethe penetration of an organic material. Such an organic modifier may be,for example, dimethyl benzyl hydrogenated tallow quaternary ammonium,dimethyl hydrogenated tallow quaternary ammonium, methyl tallowbis-2-hydroxyethyl quaternary ammonium, dimethyl hydrogenated tallow2-ethylhexyl quaternary ammonium, dimethyl dehydrogenated tallowquaternary ammonium, or mixtures thereof.

A content of the moisture blocker may be suitably selected byconsidering a desired blocking property without particular limitation.

In addition to the above-described components, various additives may beincluded according to its use and a process of manufacturing anencapsulation film that will be described below. For example, theencapsulation layer may include a curable material, a crosslinkingagent, or a filler in a suitable range of content according to a desiredphysical property.

In an exemplary embodiment, the encapsulation layer may have a singlelayer or two or more layers as described above. For example, theencapsulation film may include a first layer including theabove-described encapsulation layer and a second layer including apressure-sensitive adhesive resin or adhesive resin. Thepressure-sensitive adhesive resin or adhesive resin included in thesecond layer may be the same as or different from the above-describedencapsulation resin, and may be suitably selected according to thepurpose of those of ordinary skill in the art. Also, each of the firstand second layers may include or not include the moisture absorbent.

In an exemplary embodiment, in addition to the above-described resin,the first or second layer may include another component, for example,the above-described active energy ray polymerizable compound, aheat-curable compound, a radical initiator, a tackifier, a moistureabsorbent, a moisture blocker, a dispersant or a silane compound, andthe compositions of the first and second layers may be the same as ordifferent from each other. Also, the second layer may include a curablematerial, a curing agent or a filler in a suitable content according toa desired physical property. Meanwhile, since the encapsulation film isapplied to encapsulate an organic electronic element, a content of themoisture absorbent may be controlled by considering damage to theelement. For example, a small amount or none of the moisture absorbentmay be included in the layer in contact with the element. In oneexemplary embodiment, the second layer in contact with the element mayinclude 0 to 20% of the moisture absorbent with respect to the totalweight of the moisture absorbent contained in the encapsulation film.Also, the first layer not in contact with the element may include 80 to100% of the moisture absorbent with respect to the total weight of themoisture absorbent contained in the encapsulation film.

A sequence of stacking the second layer and additionally stacking thefirst layer is not particularly limited. For example, the second layermay be formed on the first layer, or on the contrary, the first layermay be formed on the second layer. Also, the encapsulation layer may becomposed of three or more layers, and for example, two or more of thefirst layers may be included, or two or more of the second layers may beincluded.

Also, when formed to a thickness of 100 μm, the encapsulation filmaccording to the present application may have a water vapor transmissionrate (WVTR) of 50, 40, 30, 20 or 10 g/m²·day or less, which is measuredin a thickness direction of the film at 100° F. and a relative humidityof 100%. As the compositions or crosslinking conditions of the metallayer and the encapsulation layer are adjusted to have such a WVTR, whenthe encapsulation film is applied to the encapsulation or capsulationstructure of the electronic device, the encapsulation or capsulationstructure may effectively block moisture or oxygen which has permeatedfrom the outside, and thus stably protect the element. As the WVTR islower, a more excellent moisture blocking property may be exhibited, andtherefore, the lower limit may be, but is not particularly limited to,for example, 0 g/m²·day.

The encapsulation film may further include a base film or release film(hereinafter, probably referred to as a “first film”), and have astructure in which the encapsulation layer is formed on the base orrelease film. Also, the structure may further include a base or releasefilm (hereinafter, also referred to as a “second film”) formed on theprotective layer.

A specific type of the first film capable of being used in the presentapplication is not particularly limited. In the present application, asthe first film, for example, a general polymer film used in the art maybe used. In the present application, for example, as the base or releasefilm, a polyethylene terephthalate film, a polytetrafluoroethylene film,a polyethylene film, a polypropylene film, a polybutene film, apolybutadiene film, a vinyl chloride copolymer film, a polyurethanefilm, an ethylene-vinyl acetate film, an ethylene-propylene copolymerfilm, an ethylene-acrylic acid ethyl copolymer film, an ethylene-acrylicacid methyl copolymer film or a polyimide film may be used. Also, one orboth surfaces of the base film or release film of the presentapplication may be treated by a suitable releasing treatment. As anexample of a releasing agent used for the releasing treatment of thebase film, an alkyd-, silicon-, fluorine-, unsaturated ester-,polyolefin- or wax-based agent may be used, and for thermal resistance,an alkyd-, silicon- or fluorine-based releasing agent may be used, butthe present application is not limited thereto.

In the present application, the thickness of the base film or releasefilm (the first film) is not particularly limited, and may be suitablyselected according to use. For example, in the present application, thethickness of the first film may be about 10 to 500 μm, and preferablyabout 20 to 200 μm. When the thickness is less than 10 μm, the base filmmay be easily deformed in the manufacturing process, and when thethickness is more than 500 μm, economic feasibility is reduced.

A thickness of the encapsulation layer included in the encapsulationfilm of the present application is not particularly limited, and may besuitably selected according to the following condition by consideringthe use of the film. A thickness of the pressure-sensitive adhesivelayer may be about 5 to 200 μm, and preferably about 5 to 100 μm. Whenthe thickness of the encapsulation layer is less than 5 μm, a sufficientadhesive property may not be ensured, and when the thickness of theencapsulation layer is more than 200 μm, it is difficult to ensureprocessability, the thickness is expanded due to moisture reactivity,resulting in damage to a deposition film of an organic light emittingelement, and the economic feasibility is deceased.

The present application also relates to a method of manufacturing anencapsulation film. The exemplary encapsulation film may be manufacturedby molding the encapsulation layer in a film or sheet form.

In an exemplary embodiment, the method may include applying a coatingsolution including a component constituting the above-describedpressure-sensitive adhesive layer to a base or release film in a sheetor film form, and drying the applied coating solution.

The coating solution may be prepared by dissolving or dispersing thecomponents of each encapsulation layer described above in a suitablesolvent. In an exemplary embodiment, the encapsulation layer may beformed by dissolving or dispersing the moisture absorbent or filler in asolvent when needed, and mixing the moisture absorbent or filler with anencapsulation resin after grinding.

A type of the solvent used in the preparation of the coating solution isnot particularly limited. However, when a drying time of the solvent istoo long or drying at a high temperature is needed, problems in terms ofworkability or durability of the encapsulation film may occur, andtherefore a solvent having a volatilization temperature of 150° C. orless may be used. In consideration of film moldability, a small amountof a solvent having the above range or more of a volatilizationtemperature may be mixed. As the solvent, one or two or more ofmethylethylketone (MEK), acetone, toluene, dimethylformamide (DMF),methylcellosolve (MCS), tetrahydrofuran (THF), xylene andN-methylpyrrolidone (NMP) may be used, but the present application isnot limited thereto.

A method of applying the coating solution to the base or release film isnot particularly limited, and thus may be, for example, a known coatingmethod such as knife coating, roll coating, spray coating, gravurecoating, curtain coating, comma coating or lip coating.

The applied coating solution is dried, the solvent is volatilized, andthus a pressure-sensitive adhesive layer may be formed. The drying maybe performed, for example, at 70 to 150° C. for 1 to 10 minutes. Thedrying conditions may be changed by considering the used solvent.

A method of stacking a first layer and a second layer is notparticularly limited. For example, the first layer and the second layer,which are formed on respective release films, may be laminated, therebyforming a multi-layered encapsulation film, or the second layer may beformed directly on the first layer or vice versa.

After drying, a metal layer may be formed on the encapsulation layer. Amethod of forming the metal layer may be a technique known in the art.For example, the metal layer may be formed of metal foil, or formed bydepositing a metal on a protective layer. For example, the metal layermay be formed by electrolysis or rolling.

The present application also relates to an OED. The OED, as shown inFIG. 2, may include a substrate 21; an organic electronic element 22formed on the substrate 21; and the above-described encapsulation film10 for encapsulating the organic electronic element 22. Theencapsulation film may encapsulate entire surfaces, for example, top andside surfaces of the organic electronic element. The encapsulation filmmay include an encapsulation layer containing a pressure-sensitiveadhesive composition or adhesive composition in a crosslinked state.Also, the OED may be formed such that the encapsulation layer is incontact with the top surface of the organic electronic element.

Here, the organic electronic element may be, for example, an organiclight emitting element.

Also, the present application relates to a method of manufacturing anOED. The OED may be manufactured using, for example, the encapsulationfilm.

The encapsulation layer may be formed as a structure exhibiting anexcellent moisture blocking property in the OED, and effectively fixingand supporting the substrate and the metal layer.

Also, the encapsulation layer may be formed to be a stable encapsulationlayer whether or not the OED is a top emission or bottom emission type.

The term “encapsulation layer” used herein may be a pressure-sensitiveadhesive covering all of the top and side surfaces of the organicelectronic element.

To manufacture the OED, for example, applying the above-describedencapsulation film to the substrate on which the organic electronicelement is formed to cover the entire surfaces of the organic electronicelement; and curing the encapsulation film may be included. The curingof the encapsulation film means curing of the encapsulation layer.

The term “curing” used herein may refer to the preparation of apressure-sensitive adhesive by crosslinking the pressure-sensitiveadhesive composition of the present application through heating or UVirradiation. Also, the curing may mean that the adhesive composition isprepared in an adhesive type.

In detail, the organic electronic element may be formed by forming atransparent electrode on a glass or polymer film used as a substratethrough vacuum deposition or sputtering, forming a light emittingorganic material layer, for example, consisting of a hole transportlayer, an emitting layer and an electron transport layer on thetransparent electrode, and further forming an electrode layer thereon.Subsequently, the encapsulation film may be disposed so that theencapsulation layer covers the entire surfaces of the organic electronicelement of the substrate undergoing the above-described process.

Effect

An encapsulation film of the present application may be applied toencapsulate or capsulate an OED such as an OLED. The film can also beformed to have a structure for effectively blocking moisture or oxygenentering the OED from the outside, and has excellent mechanicalproperties such as handleability and processability.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of an encapsulation film according toan exemplary embodiment of the present application; and

FIG. 2 is a cross-sectional view of an OED according to an exemplaryembodiment of the present application.

EXPLANATION OF REFERENCE NUMERALS

10: encapsulation film

11: encapsulation layer

12: metal layer

13: protective layer

21: substrate

22: organic electronic element

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Hereinafter, the present application will be described in further detailwith reference to examples according to the present application andcomparative examples not according to the present application, and thescope of the present application is not limited to the followingexamples.

Example 1 Preparation of Solution for Encapsulation Layer

A coating solution was prepared by adding 50 g of butyl rubber (Br068,EXXON) as an encapsulation resin, 24 g of a hydrogenated hydrocarbonresin (Eastotac H-100L) as a tackifier, 15 g of 2-(2-ethoxyethoxy)ethylacrylate as a monofunctional acrylate, 10 g of trimethylolpropanetriacrylate as a multifunctional active energy ray polymerizablecompound and 1 g of 2,2-dimethoxy-1,2-diphenylethane-1-one (Irgacure651, Ciba) as a radical initiator, and diluting the resultant mixturewith toluene to a solid content of about 15 wt %.

Preparation of Protective Layer and Metal Layer

A coating solution for a protective layer was prepared by mixing Sylgard184 (polydimethylsiloxane) manufactured by Dow Corning in a weight ratioof a main material to a curing agent of 5:1, and the coating solutionwas applied to a 50-μm aluminum film in a thickness of 100 μm.

Manufacture of Encapsulation Film

An encapsulation film was manufactured by forming an encapsulation layerhaving a thickness of 50 μm by coating a release surface of a releasePET with the prepared solution for the encapsulation layer and dryingthe coated surface in an oven at 100° C. for 15 minutes, and laminatingthe encapsulation layer with the aluminum film. Physical properties ofthe film sample irradiated with UV rays at 2 J/cm² were measured.

Example 2

An encapsulation film was formed by the same method as described inExample 1, except that a metal layer was formed to a thickness of 30 μm.

Example 3

An encapsulation film was formed by the same method as described inExample 1, except that a metal layer was formed to a thickness of 20 μm.

Example 4

An encapsulation film was formed by the same method as described inExample 1, except that a protective layer was formed to a thickness of50 μm.

Comparative Example 1

An encapsulation film was formed by the same method as described inExample 1, except that a metal layer (SUS304) having a thickness of 700μm was used and a protective layer was not used.

Comparative Example 2

An encapsulation film was formed by the same method as described inExample 1, except that polyethylene terephthalate was used as aprotective layer.

Experimental Example 1—Warpage of Panel

Each of the encapsulation films manufactured in the examples and thecomparative examples was disposed on a substrate, stored in an oven at100° C. for 1 hour and then the warpage of the film was measured at roomtemperature. In detail, a distance (a degree of lifting of the sidesurface of the film) between a side surface of the film which hadwarpage and a bottom surface was measured.

Experimental Example 2—Tensile Modulus

Tensile moduli of the protective layer, the metal layer and theencapsulation layer prepared in each of the examples and the comparativeexamples were measured. A specimen was prepared by being cut in a sizeof 50 mm×10 mm (length×width) in a lengthwise direction, which was thecoating direction during the formation of the protective layer, themetal layer and the encapsulation layer, and both ends of the specimenwere taped in a lengthwise direction until only 25 mm of the specimenremained. Subsequently, the specimen was stretched by grabbing the tapedparts at 25° C. and a tensile speed of 1 mm/min to measure a tensilemodulus.

TABLE 1 Tensile modulus (MPa) Protective Metal Encapsulation Warpagelayer layer layer (mm) Example 1 2 69,000 5 4 Example 2 2 69,000 5 2.7Example 3 2 69,000 5 1.9 Example 4 2 69,000 5 1.9 Comparative — 203,0005 4.8 Example 1 Comparative 2350 69,000 5 5 Example 2

In Comparative Example 2, PET was used as a protective layer, and eventhough PET had a coefficient of linear expansion of about 59.4ppm/K(polydimethylsiloxane: about 310 ppm/K), the tensile modulus wasout of the above range, resulting in considerable warpage of the film.

What is claimed is:
 1. An encapsulation film for an organic electronicelement, comprising: a protective layer having a tensile modulus of 0.01to 500 MPa at 25° C.; a metal layer formed on one surface of theprotective layer; and an encapsulation layer formed on the metal layer,wherein the protective layer has a thickness of 40 to 400 μm, whereinthe metal layer has a thickness of 10 to 100 μm, and wherein theprotective layer and the metal layer satisfy General Equation 1:T _(p) /T _(m)≧1  [General Equation 1] where T_(p) is a thickness of theprotective layer, and T_(m) is a thickness of the metal layer.
 2. Thefilm of claim 1, wherein the metal layer has a tensile modulus of 10,000to 250,000 MPa at 25° C.
 3. The film of claim 1, wherein the metal layercomprises any one of a metal, a metal oxide, a metal nitride, a metalcarbide, a metal oxynitride, a metal oxyboride, and mixtures thereof. 4.The film of claim 1, wherein the metal layer comprises any one ofaluminum, copper, nickel, silicon oxide, aluminum oxide, titanium oxide,indium oxide, tin oxide, indium tin oxide, tantalum oxide, zirconiumoxide, niobium oxide, and mixtures thereof.
 5. The film of claim 1,wherein the protective layer comprises one or more resin componentsselected from the group consisting of polyorganosiloxane, a polyimide, astyrene-based resin or elastomer thereof, a polyolefin-based resin orelastomer thereof, a polyoxyalkylene-based resin or elastomer thereof, apolyester-based resin or elastomer thereof, a polyvinylchloride-basedresin or elastomer thereof, a polycarbonate-based resin or elastomerthereof, a polyphenylenesulfide-based resin or elastomer thereof, apolyamide-based resin or elastomer thereof, or elastomer thereof, anepoxy-based resin or elastomer thereof, a silicone-based resin orelastomer thereof, and a fluorine-based resin or elastomer thereof. 6.The film of claim 1, wherein the encapsulation layer is formed with asingle layer or two or more layers.
 7. The film of claim 1, wherein theencapsulation layer comprises an encapsulation resin.
 8. The film ofclaim 7, wherein the encapsulation layer further comprises an activeenergy ray polymerizable compound.
 9. The film of claim 1, wherein theencapsulation layer comprises a moisture absorbent.
 10. An organicelectronic device, comprising: a substrate; an organic electronicelement formed on the substrate; and the encapsulation film of claim 1,which encapsulates the organic electronic element.
 11. The device ofclaim 10, wherein the encapsulation layer of the encapsulation filmcovers the entire surfaces of the organic electronic element.
 12. Amethod of manufacturing an organic electronic device, comprising:applying the encapsulation film of claim 1 to a surface on which anorganic electronic element is formed to cover entire surfaces of theorganic electronic element; and curing the encapsulation film.